diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/kernel/net.c | 46 |
1 files changed, 33 insertions, 13 deletions
diff --git a/src/kernel/net.c b/src/kernel/net.c index 54accb6..fcea31b 100644 --- a/src/kernel/net.c +++ b/src/kernel/net.c @@ -86,7 +86,7 @@ static bool dnbd3_execute_handshake(dnbd3_device_t *dev, struct socket *sock, struct sockaddr_storage *addr, uint16_t *remote_version, bool copy_image_info); static bool dnbd3_request_test_block(dnbd3_device_t *dev, struct sockaddr_storage *addr, - struct socket *sock); + struct socket *sock, u64 test_start, u32 test_size); static bool dnbd3_send_empty_request(dnbd3_device_t *dev, u16 cmd); @@ -193,10 +193,14 @@ static void dnbd3_internal_discover(dnbd3_device_t *dev) { struct socket *sock, *best_sock = NULL; dnbd3_alt_server_t *alt; + struct request *blk_request; struct sockaddr_storage host_compare, best_server; uint16_t remote_version; ktime_t start, end; unsigned long rtt = 0, best_rtt = 0; + u64 test_start = 0; + u32 test_size = RTT_BLOCK_SIZE; + unsigned long irqflags; int i, j, k, isize, fails, rtt_threshold; int do_change = 0; u8 check_order[NUMBER_SERVERS]; @@ -254,6 +258,24 @@ static void dnbd3_internal_discover(dnbd3_device_t *dev) if (!dnbd3_execute_handshake(dev, sock, &host_compare, &remote_version, false)) goto error; + if (dev->panic) { + // In panic mode, use next pending request for testing, this has a higher chance of + // filtering out a server which can't actually handle our requests, instead of just + // requesting the very first block which should be cached by every server. + spin_lock_irqsave(&dev->send_queue_lock, irqflags); + if (!list_empty(&dev->send_queue)) { + blk_request = list_entry(dev->send_queue.next, struct request, queuelist); + test_start = blk_rq_pos(blk_request) << 9; /* sectors to bytes */ + test_size = blk_rq_bytes(blk_request); + } + spin_unlock_irqrestore(&dev->send_queue_lock, irqflags); + } + + // actual rtt measurement is just the first block request and reply + start = ktime_get_real(); + if (!dnbd3_request_test_block(dev, &host_compare, sock, test_start, test_size)) + goto error; + end = ktime_get_real(); // panic mode, take first responding server if (dev->panic) { @@ -264,7 +286,10 @@ static void dnbd3_internal_discover(dnbd3_device_t *dev) // Check global flag, a connect might have been in progress if (best_sock != NULL) sock_release(best_sock); - set_socket_timeout(sock, false, SOCKET_TIMEOUT_RECV * 1000 + 1000); + set_socket_timeout(sock, false, MAX( + SOCKET_TIMEOUT_RECV * 1000, + (int)ktime_ms_delta(end, start) + ) + 1000); if (dnbd3_set_primary_connection(dev, sock, &host_compare, remote_version) != 0) sock_release(sock); dnbd3_flag_reset(dev->connection_lock); @@ -272,12 +297,6 @@ static void dnbd3_internal_discover(dnbd3_device_t *dev) } } - // actual rtt measurement is just the first block requests and reply - start = ktime_get_real(); - if (!dnbd3_request_test_block(dev, &host_compare, sock)) - goto error; - end = ktime_get_real(); - mutex_lock(&dev->alt_servers_lock); if (is_same_server(&dev->alt_servers[i].host, &host_compare)) { dev->alt_servers[i].protocol_version = remote_version; @@ -924,23 +943,24 @@ static bool dnbd3_drain_socket(dnbd3_device_t *dev, struct socket *sock, int byt return true; } -static bool dnbd3_request_test_block(dnbd3_device_t *dev, struct sockaddr_storage *addr, struct socket *sock) +static bool dnbd3_request_test_block(dnbd3_device_t *dev, struct sockaddr_storage *addr, + struct socket *sock, u64 test_start, u32 test_size) { dnbd3_reply_t reply_hdr; // Request block - if (!dnbd3_send_request(sock, CMD_GET_BLOCK, 0, 0, RTT_BLOCK_SIZE)) { + if (!dnbd3_send_request(sock, CMD_GET_BLOCK, 0, test_start, test_size)) { dnbd3_err_dbg_host(dev, addr, "requesting test block failed\n"); return false; } - // receive net reply + // receive reply header if (dnbd3_recv_reply(sock, &reply_hdr) != sizeof(reply_hdr)) { dnbd3_err_dbg_host(dev, addr, "receiving test block header packet failed\n"); return false; } if (reply_hdr.magic != dnbd3_packet_magic || reply_hdr.cmd != CMD_GET_BLOCK - || reply_hdr.size != RTT_BLOCK_SIZE || reply_hdr.handle != 0) { + || reply_hdr.size != test_size || reply_hdr.handle != 0) { dnbd3_err_dbg_host(dev, addr, "unexpected reply to block request: cmd=%d, size=%d, handle=%llu (discover)\n", (int)reply_hdr.cmd, (int)reply_hdr.size, reply_hdr.handle); @@ -948,7 +968,7 @@ static bool dnbd3_request_test_block(dnbd3_device_t *dev, struct sockaddr_storag } // receive data - return dnbd3_drain_socket(dev, sock, RTT_BLOCK_SIZE); + return dnbd3_drain_socket(dev, sock, test_size); } #undef dnbd3_err_dbg_host |